LOCATION VALLETTA WAEstablished Series
TAXONOMIC CLASS: Medial-skeletal, ferrihydritic, mesic Typic Hapludands
TYPICAL PEDON: Valletta extremely gravelly medial loam - forestland, on a 78 percent south-facing slope at an elevation of 1,530 feet in a western hemlock/salal-western swordfern plant association. (When described on August 1, 1990 the soil was moist throughout. Colors are for moist soils unless otherwise stated. All textures are apparent field textures.)
Oi--0 to 3 inches; slightly decomposed needles, leaves, twigs and cones; abrupt smooth boundary. (1 to 3 inches thick)
A--3 to 10 inches; dark brown (7.5YR 4/4) extremely gravelly medial loam, strong brown (7.5YR 5/6) dry; weak very fine subangular blocky and weak very fine and fine granular structure; slightly hard, friable, slightly sticky and slightly plastic; weakly smeary; many very fine and fine and common medium and coarse roots; common very fine and fine tubular and irregular pores; 55 percent gravel, 15 percent cobbles; very strongly acid (pH 4.8); clear smooth boundary. (4 to 8 inches thick)
Bw1--10 to 21 inches; strong brown (7.5YR 4/6) extremely gravelly medial loam, reddish yellow (7.5YR 6/6) dry; weak very fine subangular blocky and weak very fine and fine granular structure; slightly hard, friable, slightly sticky and nonplastic; weakly smeary; common very fine, fine, medium, and coarse roots; common very fine and fine irregular pores; 45 percent gravel, 20 percent cobbles; strongly acid (pH 5.2); clear wavy boundary.
Bw2--21 to 38 inches; dark yellowish brown (10YR 4/6) extremely gravelly medial sandy loam, brownish yellow (10YR 6/6) dry; weak very fine subangular blocky and weak very fine and fine granular structure; slightly hard, friable, nonsticky and nonplastic; weakly smeary; common very fine and fine and few medium and coarse roots; common very fine and fine irregular pores; 55 percent gravel, 20 percent cobbles; strongly acid (pH 5.4); clear wavy boundary.
Bw3--38 to 63 inches; dark yellowish brown (10YR 4/6) extremely gravelly sandy loam, yellow (10YR 7/6) dry; weak very fine subangular blocky and weak very fine and fine granular structure; slightly hard, friable, nonsticky and nonplastic; few very fine and fine roots; few very fine irregular pores; 55 percent gravel, 15 percent cobbles; strongly acid (pH 5.4). (Combined thickness of the Bw horizon is 50 to 60 inches)
TYPE LOCATION: Mason County, Washington; about 1 mile north of the Hammahamma Campground, about 530 feet west and 395 feet south of the northeast corner of section 1, T. 24 N., R. 4 W. ( Latitude 47 degrees, 36 minutes, 20 seconds N., Longitude 123 degrees, 07 minutes, 29 seconds W.)
RANGE IN CHARACTERISTICS: Mean annual soil temperature is 47 to 51 degrees F. These soils are usually moist, and are dry 30 to 45 consecutive days in the soil moisture control section; udic moisture regime. Depth to bedrock is greater than 60 inches. The particle-control section has andic soil properties with a cumulative thickness of 20 to 40 inches. The andic soil material has an estimated moist bulk density of 0.70 to 0.90 g/cc., acid-oxalate extractable aluminum plus one-half of the acid-oxalate extractable iron of 2 to 3 percent, phosphate retention of 85 to 100 percent, 15-bar water retention of 12 to 25 percent for air dried samples, and 60 to 90 percent rock fragments by volume. Layers or horizons having 15 bar water values of less than 15 percent are less than 10 inches thick. Acid oxalate extractable iron is 1.5 to 3.0 percent.
The A horizon has hue of 10YR or 7.5YR, value of 3 or 4 moist and 4 or 5 dry, and chroma of 3 or 4 moist and 4 or 6 dry. It has 5 to 10 percent organic matter. It has 2 to 4 cmol/kg of aluminum.
The Bw horizon has hue of 10YR or 7.5YR, value of 3 or 4 moist and 5 through 7 dry, and chroma of 4 or 6 moist or dry. It is extremely gravelly medial sandy loam, extremely gravelly medial loam, or extremely cobbly medial sandy loam. It has 1 to 2 cmol/kg of aluminum. It has 1 to 5 percent organic matter. Reaction is moderately or strongly acid. The lower part of the Bw horizon has an estimated moist bulk density of 0.90 to 1.10 g/cc.
COMPETING SERIES: These are the Lenacreek and Nedhill series. Lenacreek soils are 20 to 40 inches to a lithic contact. Nedhill soils are 20 to 40 inches to densic material (glacial till).
GEOGRAPHIC SETTING: Valletta soils are on mountains. Slopes are 60 to 90 percent. The soils formed in colluvium from marine basalt and associated volcanic rocks. Elevations are 500 to 1,900 feet. Average annual precipitation is 70 to 150 inches. Average annual temperature is 45 to 49 degrees F. Frost free season is 170 to 190 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Dosewallips, Fircreek, Govey, and the competing Lenacreek soils. Dosewallips soils are on mountain slopes an are shallow to bedrock. Fircreek and Govey soils are on glaciated mountain slopes and glacial valleys and are moderately deep to a cemented layer.
DRAINAGE AND PERMEABILITY: Well drained; moderately rapid permeability.
USE AND VEGETATION: Timber production, wildlife habitat, recreation, and watershed. Native vegetation is Douglas-fir, western hemlock, salal, Oregon-grape, and western swordfern.
DISTRIBUTION AND EXTENT: Olympic Mountains, Mason and Jefferson Counties, Washington; MLRA 1. Series is of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Mason County, Washington, 2000; Olympic National Forest.
REMARKS: Diagnostic horizons and features recognized in this pedon are an ochric epipedon, a cambic horizon from 10 to 63 inches and andic soil properties from 3 to 38 inches. The particle-size control section is from 3 to 43 inches (A and Bw horizons).
All depths to diagnostic horizons and other features are measured from the top of the first mineral horizon.